1980 honda cb750k... worth buying?

[curtistckr]

i am about to trade a truck for this bike, but dont really know much about it. do any of you? let me know if im making a mistake. thanks

[Grizzly]

Hi

The dohc CB750 K is a good bike and is very enjoyable on todays roads. When they first came out in 79 they had a cam chain issue but Honda soon had that sorted.A couple of my mates had them new and thrashed them all over the place with no further problems.

Start the bike from cold let it warm up to its normal operating temperature where it should tick over quietly and evenly at about 1100rpm give or take a 100. If the bigends or mains are noisey walk away. If the cam chain is noisey it might just need adjusting but beware. Rev the motor and check for smoke out of the pipes, there should not be any. The clutch might rattle. If it does just pull in the clutch lever and the noise should go. As the old saying goes they all do that sir.  if it does not then beware.

If you are happy with the motor then it is simply the usual checks for bearings, crash damage and consumeables etc.

Are you making a mistake? Can't answer that one. I think that if the bike is ok then you will love riding it!

Cheers
Grizzly

[sono]

Compression testing is extremely simple to perform and it tells a lot on the engine condition. If compression is uneven or below minimal specs (lower than 7 bars) walk away. Except maybe if only the engine valves require a basic adjustment, it is rarely economical to restore compression on such a four cylinder engine and it is completely nuts to consider rebuiling the whole engine (I mean, you must be maddly in love with it, have a DEEEEP pocket and plenty of time).

I recently had my Honda CM400T 1980 compression restored to specs because the bottom of the engine was in good condition and I had the chance to find for cheap spare cylinders and complete engine head in excellent condition that I got refurbished as new by an old mechanic. A Four cylinder has twice as many parts to change, cylinders to bore and valves to rebuild.

It was a success, but it ended up more than twice the price of a used replacement motor even if the engine did not even need to be taken out of the frame on mine. This is why I consider cost of rebuilding a Four cylinder much to high to be economical.

[curtistckr]

i took your advice, both of you, and im glad i did. off the bat i started it and it was spewing white smoke from the exaust, the engine mounts (thats right the mounts) were loose, and the clutch was damn near falling off it was so loose. the guy was trying to convince me all of that was normal, and okay. needless to say i walked away, and decided to go with something a little newer, so i am now the proud daddy of a 1999 honda CBR 900. i wake up at night just wanting to ride! i love her! thanks again for the advice fellas.

[Grizzly]

Nice one.
Enjoy the Blade